SAN FRANCISCO (KCBS) – An assisted living facility for formerly homeless senior citizens was evacuated Thursday so that a bomb squad could investigate a suspicious device, San Francisco police said.

The device was discovered as police helped evacuate part of 44 McAlister smoke was reported coming from one of the building’s garbage chute at 6:30 a.m., according to a San Francisco Police Department spokesman.

Firefighters who put out the fire in the chute also found one of the residents left a threatening note in his room and had tried to disable the buildings smoke detectors and sprinklers.

All 150 residents of the building, known as the Civic Center Residence, were evacuated as a precaution.

Police also closed the first block of McAllister between 7th and Jones streets, not far from Market Street, to both vehicle traffic and pedestrians for several hours. They reopened just before 10 a.m.

There have been no reports of any injuries.

The man who lived in the room where the note was found has been detained for questioning, police said.

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